Moving stairway



June 24,1930. M Q SCHWAB 1,767,945

MOVING STAIRWAY INVENTOR ATTORNEY June 24, 1

M. C. SCHWAB MOVING STAIRWAY Filed May 15, 1928 I F72 G74 75 2 Sheets-Sheet 2 FIG. 7

' INVENTOR A'I'TOIQNEYI Patented June 24, 1930 UNITED `STA'rEs PATENT OFFICE MARTIN C. SCHWAB, OF CHICAGO, ILLINOIS, ASSIGNOR TO OTIS ELEVATOR COMPANY, OF YORK, N. Y., A. CORPORATION F NEW JERSEY MOVING STAIRWAY Application led May 15, 1928. Serial No. 277,993.

This invention relates to moving stairways.

It is now common to use escalators or moving stairways to carry traic from a higher level to a lower level as well as from a lower level to a higher level. It is also becoming the practice for more economical and expedient use of the moving stairway to use the same moving stairway to carry traiiic up part of the time of operation and down the other part of the time of operation. From .a hurried glance at a moving stairway it is almost irnpossible to ascertain in which direction it is moving, and when the stairway is operated in up and Idown directions alternately during the day, considerable confusion results around the landings from this inability to quickly ascertain the direction of movement of the stairway. It is also possible that accidents may occur when using these reversible 2o moving stairways as a result'of people getting on at the top landing of a stairway that was moving up in the belief that it was going down, and as a result of people getting on at the bottom landing of a stairway that was moving down in the belief that it wasgoing up.

One feature of this invention is the provision of an indicating system for moving stairvways to prevent such confusions, delays and 3o accidents, which system indicates at the landings the direction of motion of the stairway.

A second feature of this invention is the provision of a direction-of-motion indicating system for moving stairways which is positively operated in conjunction with the motion-producing controls for the stairway.

Other features and advantages will become apparent from the following description and theappended drawings.

In the drawings Figure 1 is a plan view of the moving stairway showing the direction-of-motion indicators;

Figure 2 is a vertical elevation of the moving stairway partly broken away to illustrate certain features of construction thereof; l Y

Figure 3 is a plan view of the indicator Figure 4 is a sectional view of the indica- 50 tor taken along lines 4-4 of Figure 3;

Figure 5 is a sectional View of the indicator taken along lines 5-5 of Figure 3;

Figure 6 is a straight wiring diagram of the motor and control circuits and the direction-of-motion indicator circuits for the stairway; and

Figure 7 is an elevation of the control panel showing the magnets, relays and contacts.

Referring to Figures 1 to 5, a moving stairway 1 extends between landings 2 and 3. The stairway comprises steps 4 having rollers 5 supported at one end of each step and secured in an endless chain 6 which is driven by sprocket 7. Rollers 5 ride over a suitable track 8. The other end of steps 4 have risers 9 on which are mounted rollers 10 which ride over another suitable trackll.

Balustrades 12 for the stairway each have endless handrails 13 which are driven from the shaft 14 on which is secured the sprocket 7. Shaft 14 is driven by motor 15 through reducing worm and worm wheel system 16 and chain and sprocket system 17. There is a brake 30 which operates on the shaft of the motor 15.

At each end of each balustrade there is a direction-of-motion indicator 18. Y In the embodiment illustrated, this indicator consists of a metal box 19 inserted in the woodwork of the balustrade so that the .frame 20 of the' box is approximately flush with the woodwork. A screen 21 of suitable material, as dark ground glass, is secured over one side of box 19 by frame 20. Painted or otherwise suitably aflixed to screen 21 are the down direction symbol 22 and the up direction symbol 23. The indications thereof may be of different colors, such as green for up and red for down. Contained within boxes 19, behind each symbol 22 there is an electric light bulb 24 and behind each symbol 23 there is an electric light bulb 25, and between bulbs 24 and 25, in each indicator 18 there is a screen 26. Thus, when bulbs 24 are lighted, downsymbols 22 only will be visible to prospective passengers approaching the landings. Alternatively, when bulbs 25 are lighted, only up A symbols 23 will be visible.

In order to insure the posltive response of indicators 18 to changes in the directionof at each landing. Such control box comprises switches is as follows:

stairway motion, bulbs 24 and 25 are operated by some part of the moving stairway or of the control apparatus, for example, by auxiliary contacts on the reversing switches. This will be more fully explained below.

The o eration of the stairway may be controlled fiom either landing by means of a push button control box 31 which is provlded an 11p-start push button 32, a down-start push button 33 and a stop push button 34. Ifdesired, a cover may be supplied for the control boxes, through whichv only the stop push button projects. The push buttons 32 are in parallel, the push buttons 33 are in parallel and the stop buttons 34 are in series, as may be seen from Figure 6.

Figure 6 shows a straight diagram of the motor and controlling circuits for the moving stairway, in which each electromagnetic switch, comprising an actuating coil and the contacts it opens or closes, has been given a letter in addition to the usual reference numerals, so that althou hwthe parts of a switch have been separated or simplicityin showing the circuits, they may still be identified by means of the common letter.

The electromagnetic switches are shown in their deenergized positions, hence the contacts which are open are the forward contacts and the contacts whichf are closed arethe back contacts. To further aid the reading of the diagram, the stationary contacts 'are illustrated in cross section. The physical set-up of the coils and contacts is shown in Figure 7.

The designation of the electromagnetic A-Up direction switch,

B-Down direction switch,

D-Final accelerating switch,

lil-Accelerating switch,

F-Overload switch,

G-Excess voltage switch.

35 is the armature of driving motor 15 across which is connected stopping resistance y37. Motor 15 is provided with shunt field 36 and starting resistance 38. Across brake release coil 39 is connected parallel brake resistance PBR and in series with coil 39 is cooling or auxiliary brake resistance ABR; the short circuit of which through contacts 40 is relieved when these contacts are mechanically opened by the operation of the brake releasing mechanism.

A 41 is the actuating coil for the 'up direct1on switch, which has self-holding contacts A 42, brake release contacts A 43, armature circult contacts A 44 and A 45, electric interlock contacts A 46 and A 47, and auxiliary contacts A 48.

B. 51 is the actuating coil for the down direction switch, which has self-holding contacts 52, brake release contacts B 53, armature circuit contacts B 54 and B 55, electric interlock contacts B 56 and B 57, and auxiliary contacts B 58.

E 60 is the actuating coil for the accelerating switch, which has starting-resistanceshorting contacts E 61, E 62 and E 63 and auxiliary contacts E 64, all of which contacts close successively in the order enumerated. D 65 is the actuating coil for the final accelerating switch, which has starting-resistance-shorting contacts D 66, holding contacts D 67 and auxiliary contacts D 68 and D 69. When switch D is operated to apply full voltage to the motor, contacts D 68 insert cooling resistance 7() in the circuit of coil D 65 and either coils A 41 or B 51, and contacts D 69 open up the circuit through coil E 60.

F 71 is the actuating coil of the overload switch, which has circuit opening contacts F 72. G 73 is the actuating coil of the excess armature voltage or overspeed switch, which has circuit opening contacts G 74. In the same circuit' with the contacts of the various stopping devices is-the knife switch 75 on the controller board for use in case an operator in the motor room desires to stop the stairway. He cannot start the stairway from within the room, however.,` He must go to one of the landings in order to there push the start buttons, and in so doing, he cannot fail to notice whether there is anyone on the stairway who might be injured by the starting thereof.

There are provided hold-down coils HD 81 and HD 82 as an additional safety feature to prevent operation of one of the reversing switches while the other is closed. There is also provided a main line switch 76.Y

In operation, main line switch 76 and knife switch 75 are closed, and up-start push button 32, for example, is depressed. Coil A 41 is energized and the circuit across push button 32 maintained by contacts A 42. Brake 30 is released, and contacts A 44 and A 45 close to energize armature 35. At the same time,

the system is electrically locked against movement in the reverse direction by the opening of contacts A 46 and A 47 and the energization of hold-down coil HD 81. As armature 35 gains speed, its counter electromotive force increases the energization of coil E 60, and contacts E 61, E 62, E 63 and E164 close successively. lThe first three sets of contacts directly short-out part of the startin resistance in steps. vThe last contact energizes coil D 65 which thereupon maintains itself by contacts D 67, completely shorts-out the starting resistance by contacts D 66, opens up the accelerating switch circuit by contacts D 69, and inserts cooling resistance by the opening of contacts D 68.

To stop the motion of the stairwa ,the control circuit is broken by stop push utton 34,v

the direction switch for example, whereupon to the deenergized position.-

A falls back Contacts A 44 and A 45 open to isolate arma ture 35, contacts A 47 close to connect stopping resistance 37 across the armature, and contacts A 43 open to deenergize brake release coil 39. v

The lights in the direction-o-motion indicators are also shown in Figure 6. Lights behind the up symbols are connected in series across the supply line through auxiliary contacts A 48. Lights 24 behind the down symbols are connected in series across the supply line through auxiliary contacts B 58. If desired, a resistance 78 may be used to reduce the supply voltage, and a knife switch 77 provided in the light circuits.' If it is more expedient, the lights may, of course, be in parallel instead of in series, as shown.

Auxiliary contacts A 48 close with the operation of the A switch in starting the stairway in an up direction, and hence up symbols 23 on indicators 18 are rendered visible at both the bottom and the top of the,

stairway. When the stairway is started in the down direction, symbols 22 are made visible by the closing of auxiliary contacts B 58 of the B switch. In this manner, the direction-of-motion indicators are absolutely responsive to the direction of the stairways motion. i

As many changes could be made in the above construction and many apparently Widely dili'erent embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or .shown in the accompanying ,drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is: v

In combination, a moving stairway having a balustrade on each side thereof, means to cause motion of said stairway in either the up or down direction, a direction-of-motion indicator mounted in each balustrade at each end and flush with the surface thereof, and means responsive to each starting of the moving stairway'in thel up direction'for rendering visible each up symbol in all of said indicators and responsive to each starting of v the moving stairway in the down direction for rendering visible each down symbol in all of said indicators, said last-named means being also responsive to each stopping of the stairway to render invisible all symbols in all of said indicators.

In testimony whereof, I have signed my name to this specification.

. MARTIN C. SCHWAB. 

